Sunday, 16 May 2010

Johnald's Fantastical Daily Link Splurge

Johnald's Fantastical Daily Link Splurge

Jury Reaches Decision in Brain-Scan Test Case

Posted: 14 May 2010 01:35 PM PDT


After a judge excluded brain scan evidence offered by the plaintiff, a jury quickly found for the defense in a Brooklyn sexual harassment case this week.

The case, which drew national attention following a article earlier this month, was one of the first times that fMRI brain scanning had been offered as evidence in court.

David Zevin, the plaintiff's lead attorney, had argued that his client, temp worker Cynette Wilson, had been blacklisted from assignments after complaining about sexual harassment at a work site. The plaintiff's key witness claimed his boss at the staffing agency, Edwin Medina, told him not to give Wilson any more assignments. The staffing agency denied the allegation.

To try to prove his witness was not lying, Zevin contacted the brain scanning company Cephos, which agreed to provide their fMRI lie-detection test for free. When asked several questions like, "Did Edwin Medina tell you not to place Cynette because she was too legally savvy?" the witness, according to Cephos, answered truthfully.

But the New York State Court jury felt otherwise. They deliberated for less than half an hour before finding for the defense.

"Given that the jury took so little time to deliberate, it certainly suggests that they did not believe that this witness was credible," wrote Jessica Cortes of Davis & Gilbert, lead attorney for the defense, in an e-mail to "The plaintiff's witness admitted under oath to the jury that his earlier sworn testimony — which was the basis of the plaintiff's case and her only alleged evidence of retaliation — was not true. So it certainly begs the question as to how reliable the fMRI test could be?"

But Zevin said that his witness' statements in the previous sworn testimony were minor timeline issues and that on the core issue of whether Medina had blackballed Wilson, his witness was telling the truth.

Cortes successfully argued in pretrial motions that the fMRI evidence should be excluded because it was the fundamental right of juries, not machines, to determine the credibility of witnesses, regardless of their respective accuracy. In this case, the jury's estimation of the case presumably differed from that delivered by Cephos' brain-scan report.

The line-of-attack sidestepped the lively scientific debate over the reliability of brain-scanning techniques. The judge in the Brooklyn case plans to issue a legal opinion on why he excluded the fMRI evidence within the next several days.

Meanwhile, in a Tennessee Federal court, Cephos' fMRI evidence is getting a much more thorough vetting. In a case involving Medicare and Medicaid fraud, the brain scans are going through a Daubert hearing, the Federal court process that determines the admissibility of scientific evidence. The hearing began yesterday and wrapped up this morning. A ruling will come before June 1, when the trial is slated to begin.

According to an observer at the trial who ScienceInsider's Greg Miller interviewed last night, the hearing was not clearly going in any direction.

"At the end of the day, it wasn't clear who was winning," [University of Pennsylvania cognitive neuroscientist Martha] Farah said. But she says that Judge [Tu] Pham seems determined to hear everyone out.

"I think that we are getting a fairly complete picture of what's known and not known about the validity of this method,'" Miller wrote.

If the evidence is admitted, it will be the first time fMRI evidence about the truthfulness of testimony makes it into a U.S. court.

See Also:

WiSci 2.0: Alexis Madrigal's Twitter, Tumblr, and forthcoming book on the history of green technology; Wired Science on Twitter and Facebook.

Early Birds’ Wings Probably Didn’t Flap

Posted: 14 May 2010 09:28 AM PDT


The wings were willing, but the feathers were weak. Delicate, thin-shafted plumage would have made flapping difficult if not impossible for two prehistoric birds, a new analysis of fossil feathers suggests.

sciencenews Their feathers probably would have buckled or snapped during strong flapping or sharp maneuvers, so the primitive birds may have been limited to gliding, says Robert Nudds, an evolutionary biologist at the University of Manchester in England. He and paleontologist Gareth Dyke of University College Dublin report an engineering analysis of feathers from the ancient birds Archaeopteryx and Confuciusornis in the May 14 Science.

Nudds and Dyke used a simple formula often applied to bridges and beams to estimate the load-carrying capacities of the birds' feathers, based on fossil remains. The team also looked at the feathers of four modern birds with a variety of feather and flight types — a pigeon, a gull, an albatross and a vulture.

Even though the feathers of Archaeopteryx and Confuciusornis were about the same size as those of a modern-day pigeon, they had smaller diameter shafts that rendered them much weaker.

"Even if these feathers had solid shafts, they're not very impressive," says Lawrence Witmer, a paleontologist at Ohio University in Athens who was not part of the new study. "They're so flimsy that they couldn't have supported much weight."

In straight and level flight, the lift generated by a bird's wings, tail and other flight surfaces must support the bird's weight. But during extreme maneuvers such as high-speed turns — analogous to a fighter pilot "pulling g's" — the forces on a bird's feathers are much higher, Nudds says. In those cases, birds rely on their bones and feathers having a "margin of safety" that makes them several times stronger than needed for straight and level flight.

In modern birds, feathers typically fail when forces acting perpendicular to the central shaft cause that load-bearing structure to buckle, Nudds says. To prevent this, lift-generating feathers in present-day birds are many times stronger than necessary for level flight, from a factor of around six in vultures to a factor of more than 13 in gulls. But in the ancient birds, margins were much smaller: 2.9 for Confuciusornis and four for Archaeopteryx. If these birds had feathers with partially hollow shafts similar to those of modern feathers, these margins could have been even lower, the team argues.

The ancient birds may have simply glided from one branch to another, the researchers say, or "parachuted" from high spots to low by splaying their wings and slowing their descent.

Other recent studies of Archaeopteryx — a fossil iconic of the transition from dinosaurs to birds — have also cast doubt on the creature's flying ability.

Research suggests, for example, that although Archaeopteryx had large enough feathers for flight, it didn't have the right bone structure to take the large upstroke required for efficiently powered flight, says Richard Prum, an ornithologist at Yale University.

"Not only is the shoulder joint oriented wrong for powered flight in Archaeopteryx and Confuciusornis, but the new study shows that even the feathers aren't built right for it," says Phil Senter, a paleontologist at Fayetteville State University in North Carolina. "I've thought for some time that the feathers of nonavian dinosaurs and [primitive] birds were primarily display structures, and the lack of powered flying ability is consistent with that idea," he notes.

As far as Archaeopteryx is concerned, Witmer concurs, to a degree. In recent studies, Archaeopteryx "has become less birdlike … and is starting to look like just another feathered predatory dinosaur." He notes, though, that at this point the features of Archaeopteryx still seem closer to birds than to other dinosaurs.

The lack of modern flying ability shouldn't cast poor light on Archaeopteryx, Witmer adds. "A lot of ancient birds were probably pretty clumsy." The ability to glide or parachute from one branch to another was still an advantage, he suggests: "Anything that slows an organism's descent would add to its survivability."

It's possible, Witmer notes, that some aspects of the primitive feathers yet to be recognized by scientists compensated for their structural weakness.

Image: Composite of Todd Marshall

Video: Strapping In With the Crew of the Shuttle for Launch Training

Posted: 13 May 2010 01:05 PM PDT


The STS-132 crew will buckle into the space shuttle Atlantis tomorrow before launching into orbit for a 12-day mission to the International Space Station. It is the last scheduled flight of Atlantis, and the last scheduled flight for each of the six astronauts aboard.

Earlier this month, I was at the Johnson Space Center after STS-132 commander Ken Ham invited me to join the crew on a launch-simulation training session. After spending some time in the fixed-base simulator practicing landings, Commander Ham thought it would be interesting for me to get a taste of the launch simulations in the full-motion simulator.

The motion-based simulator (MB) is similar to the full-motion simulators used to train airline pilots. There is a complete reproduction of the entire space shuttle cockpit, and screens out the windows replicate the scenery during flight. Unlike the full-motion simulators used by the airlines, the MB that trains the astronauts can tilt all the way back to simulate the launch position of the orbiter with everybody on board lying on their backs.

Inside the cockpit are Commander Ken Ham in left seat and Pilot Tony Antonelli in the right seat. Directly behind the right seat, sits Mission Specialist Garrett Reisman and, in the middle behind a center console, sits Mission Specialist Michael Good. During launch, mission specialists Piers Sellers and Steve Bowen will be in the mid-deck and did not take part in the cockpit training sessions. Though there are only four seats in the cockpit of the orbiter, there is a fifth seat in the simulator located directly behind Commander Ham's seat for observers.

After everybody is strapped in, and all loose objects are secured, the entire cockpit is tilted on to its back and the crew sits waiting for the training to begin.

There was no iconic countdown in the simulation. After confirmation over the headset with the launch crew at mission control that everything was secure and ready to go, we could hear the rumbling sound of rockets and the entire MB started to shake. The shaking is an attempt to recreate as much of the real launch conditions as possible. The full load of the sustained g forces can't be replicated, but lying on your back with everything moving around provides some of the feeling of launch.

Inside the simulator, you can feel when the solid rocket boosters detach. The shaking stops once the main engine is cut off, about eight minutes and 30 seconds into the flight. By the time the shaking stops, the simulator is returned to a level position so the crew is no longer lying on their backs.

Astronauts Tony Antonelli, Michael Good and Garrett Reisman during a training debrief

Astronauts Tony Antonelli, Michael Good and Garrett Reisman during a training debrief

Over the course of several hours, the crew rehearsed several launch emergency scenarios, some of them stacked one after the other during a single session. After each session, the crew debrief with the trainers who are monitoring the training in a room nearby. Once the debrief was done, the MB was returned to the vertical position, a few small, loose items fall to the back of the cockpit and several minutes later, everything starts shaking and a new session begins.

From my vantage point in the extra fifth seat behind Commander Ham, watching the crew train is complete information overload. The crew remains calm through each emergency and works together like a well-oiled machine. And crew resource management takes on a whole new meaning with a four-person crew and several more on the ground at mission control. But the constant stream of information coming in from the ground crew over the headsets, the information presented inside the cockpit and the book-like checklists that are constantly referred to is incredible.

The mood during each session is all business. Each crew member is working very hard to find a solution to the wide range of emergencies that's being thrown at him. But during the short breaks between sessions, it sounds more like your average office chit-chat. The crew talks about Little League games and past work experience, though since that includes previous missions to space and flying fighter jets, it's not exactly mundane. There are plenty of jokes and laughter.

The various simulators used by the space shuttle crews are - practically speaking - the main way for astronauts to gain experience. Commander Ham and other members of the STS-132 crew have been been astronauts for more than a decade, but except for Piers Sellers, this will only be their second mission to space.

Unlike an airline or military pilot who can spend a decade gaining experience during actual flight training and missions, the relative lack of actual time in the orbiter means there is very little opportunity to gain 'on the job' experience for the astronauts. After spending only half a day in the MB watching the crew deal with everything from fires to aborted trips to orbit due to engine failures, it is apparent there is plenty of experience to be gained while only shaking 20 feet above the ground.

The crew will buckle into the real orbiter tomorrow morning. After thousands of training sessions in a variety of simulators, they are scheduled to lift off at 2:20pm EDT for a twelve day mission to the ISS. There are only three scheduled space shuttle missions remaining remaining.

Part of the ascent checklist for the space shuttle

Part of the ascent checklist for the space shuttle

Photos/Video: Jason Paur/AOPA

See Also:

Stem Cell Solution for Hearing Loss Makes Progress

Posted: 13 May 2010 12:34 PM PDT


If a few too many AC/DC concerts have you now turning up the volume on hearing aids instead of headphones, a new stem cell study in mice is reason for hope.

A team led by Stefan Heller of Stanford University set out to elucidate basic principles of how the inner ear detects sound. But they also created batches of cells that can potentially replace damaged ones in the ear. Their findings are published in the May 14 issue of Cell.

"We basically looked at how nature makes the inner ear, and what is known about the developmental processes involved, and then we just mimicked them in a test tube," Heller said.

The inner ear contains tiny hair cells that deform when sound waves hit them. Little is known about how these cells transform acoustic waves into neural signals that we interpret as sound, Heller said.

Hearing has remained mysterious compared to other sensory modalities, such as vision, because the inner ear is less accessible and there are relatively few hair cells. Like certain eye cells, hair cells generally don't regenerate once they die. Therapies using stem cells, or cells derived from embryos that can turn into myriad cell types, can potentially restore normal hearing.

Heller's team treated cells taken from mouse embryos with various signaling molecules that coaxed them into becoming cells that looked and functioned like normal hair cells. The team used a scanning electron microscope, which forms high-resolution images by bombarding items with electrons. The images revealed that cells of varying height linked together and formed bundles. When the bundles were mechanically stimulated with a slender piece of glass, the cells generated electrical currents that resemble those produced by young hair cells.

For patients who lose hair cells because of common causes, such as noise damage, toxic compounds or aging, there's a good possibility that regenerating these cells would be an alternative to using cochlear implants, said Albert Edge, a scientist at Harvard University who investigates ways to replace damaged cells in the inner ear. "If it really works well, it could be a cure rather than a treatment," he said.

The method of creating hair cells in a dish will also allow scientists to discover molecules that enable hearing. And it will offer a way to screen for drugs that spur the growth of new hair cells.

But there's still a long way to go. "Just because you have these cells in a dish, it doesn't mean that squirting them into the ear is going to make them work," Edge said.

To restore hearing, researchers still have to figure out how to produce millions of hair cells, prevent stem cells from forming tumors, and translate the work to human cells. "I'm very cautious about saying this will lead to a cure for deafness that is around the corner," Heller said. A cure is at least a decade away, he said.

Until then, the best compromise might be to sit in the back row.

Image: flickr/matthijs

Colossal Squid Is Far From Fearsome Predator

Posted: 12 May 2010 05:07 PM PDT


In the popular imagination, the colossal squid is fast and terrifying, able to dispatch whales and submarines with ease.

But the image of the squid as a nasty predator of the deep is probably more mythology than biology argue Rui Rosa of the Laboratorio Marıtimo da Guia in Lisbon and Brad Seibel of the University of Rhode Island in a new paper.

These huge squid, which can weigh more than 1,100 pounds, may have a supremely slow metabolism, allowing it to live on a measly tenth of a pound of fish flesh per day.

squid"We argue that the colossal squid is not a voracious predator capable of high-speed predator–prey interactions," they wrote in an April article in the Journal of the Marine Biological Association of the United Kingdom. "It is, rather, an ambush or sit-and-float predator that uses the hooks on its arms and tentacles to ensnare prey that unwittingly approach."

Tiny squids can be quick, but their metabolisms and movements slow as they get bigger or live deeper in the ocean. By the time you get 6,500 feet down like the colossal squid, the animals exist at a slow pace. And, unlike warm-blooded leviathans like whales, they can.

Regulating temperature has a very high energy cost, so whales have to eat a lot. The cold-blooded squid, by contrast, can simply hang out and wait for some fish to come by every once in a while.

Citation: "Slow pace of life of the Antarctic colossal squid" by Rui Rosa and Brad A. Seibel in Journal of the Marine Biological Association of the United Kingdom. doi:10.1017/S0025315409991494

From National Geographic

See Also:

WiSci 2.0: Alexis Madrigal's Twitter, Tumblr, and forthcoming book on the history of green technology; Wired Science on Twitter and Facebook.

Weird Clouds Look Even Better From Space

Posted: 12 May 2010 04:03 PM PDT

<< previous image | next image >>

Clouds are fascinating because they take on so many different, beautiful shapes and are constantly changing. Cloud-watching from Earth can be endlessly entertaining, but some of the most amazing cloud patterns can only be properly appreciated from space.

Satellites can take in thousands of miles of the Earth's surface in one shot, revealing complicated and intriguing cloud patterns we could never see from below. We've gathered here some of the best cloud formations to see from above.

Click on any of the images in this gallery for a higher-resolution version.

Von Kármán Vortex Street, Selkirk Island

The crazy-looking swirls in the image above may be one of the weirdest cloud formations that can be seen from space. The pattern is known as a von Kármán vortex street, named after Theodore von Kármán. First noticed in the laboratory by fluid dynamicists, it occurs when a more-viscous fluid flows through water and encounters a cylindrical object, which creates vortices in the flow.

Alejandro Selkirk Island, off the Chilean coast, is acting like the cylinder in the image above, taken by the Landsat 7 satellite in September 1999. A beautiful vortex street disrupts a layer of stratocumulus clouds low enough to be affected by the island, which rises a mile above sea level.

More strange and wonderful vortex streets formed by islands can be seen in the images below and in the last slide of this gallery. Below is Guadalupe Island, 21 miles off the coast of Mexico's Baja California, shot in 2000 by Landsat 7; Rishiri Island in the northern Sea of Japan, photographed by space shuttle astronauts in 2001; and Wrangel Island, above the Arctic Circle northeast of Siberia, flanked by a vortex street created by the smaller Gerald Island, imaged by NASA's Aqua satellite in August 2008.




Images: 1) Bob Cahalan/NASA, USGS. 2) NASA. 3) NASA. 4) NASA (STS100-710-182).